Gun barrel



Dec. 25, 1956 F. G. TILLANDER ETAL FOL/f5 6 r mgmL/q/vafx fyi/v Aff. UND

3) MJ. (Aa/ GUN BARREL Falke Gustav Tiilander and Ivan slund, Bofors, Sweden, assignors to Aktieboiaget Bofor's, Bofoi's, Sweden, a Swedish corporation Application December 27, 1952,'Serial`No. 328,162

Claims priority, application Sweden February 11, 1952 1o Claims. (CL :t9- 16) This invention relates'to'gun barrels. The wear and tear experienced by such barrels fas the resultof the tiring of the gun is very considerable and necessitates a frequent replacement of the barrel. For this purpose, modern weapons are 'sodesignedthat'the ibarrels can easily be exchanged. However, frequent replacement of the gun barrels is expensive and various attempts have been made to reduce thecosts caused by the exchange vof the barrels. It has for instance been proposed to vfit the barrels with an'exchangeable liner 'having vabout the same length as the barrel. While such liner'reduces the costs of an exchangeof the'barrels, "practical tests have shown that its disadvantages morethanoset its advantages. `In particular, it has been found that the required anchoring of the liner atl the rear or breech endr of the barrel causes very considerable dificultiesinhat'the extractorsofthe gun do not operate satisfactorily when a liner is anchored to the rear end of a barrel.

Broadly, the object of the present invention is to provide a novel and improved barrel design which considerably reduces the costs due to the wear and tear experienced by the barrel during the ring of the gun and which is substantially free of the disadvantages of the designs of full length liners as hitherto proposed.

States arent A careful study and examination of the wear experienced by a barrel shows that most of the wear occurs in the region of the barrel just in front of or adjacent to the forward end of the casing of a cartridge rammed into the barrel, primarily due to the effect of the hot powder gases the destructive force of which is greatest in the aforesaid region of the barrel. The occurrence of the greatest wear of the aforementioned barrel region is the more undesirable as the involved part of the barrel is also the one which is most expensive to manufacture.

Accordingly, another object of the invention is to provide a gun barrel design which permits a convenient replacement of the part of the barrel most subject to wear and tear without the necessity of anchoring a liner to the rear end of the gun barrel.

Another object of the invention is to provide a gun barrel composed of two sections or the part joined along a circumferential line situated just in front of or adjacent to the forward end of the casing of the cartridge so that it is only necessary to exchange the `less expensive front or muzzle part of the barrel when the need to do so arises.

A more specific object of the invention is to provide means by which the expenses of restoring a worn out barrel lto full usefulness are still further reduced. The said means comprise a liner fitted in the rear portion of the muzzle part of the barrel and anchored within to the muzzle section or to the front end of the breech part of the barrel.

Still other objects, features and advantages of the invention will be pointed out hereinafter and set forth in the appendant claims forming part of the application.

ln the accompanying drawing, several now preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

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In the drawing:

Fig. 1 is a perspective fragmentary view of a gun barrel according to the invention, and

Fig. 2 is a perspective, fragmentary view of Va modification of the gun barrel according to Pig. 1.

Referring rst to Fig. l, thisgure .shows a lgun barrel composed of two parts, to wit, a front or muzzle part 1 anda rear or breech part 2 including the cartridge chamber. The two parts are joined in alignment 'by a sleeveshaped member 3 having an internal thread 4 which engage corresponding external threads 5 on the adjacent ends of the two barrel parts. Sleeve 3 is secured against rotation relative to the barrel by any suitable locking means shown as a plurality of screws 6. As will 'be apparent, the provision of two barrel parts permits readily to replace the less expensivemuzzle part of the'barrel. The circumferential joining line between the Vtwo parts ofthe barrel is situated just in front of the front end of the casing 11 of a cartridge rammed into the barrel. As has been previously explained, the region of .thebarrel just in front of the forward. end of the casing of a rammed casing is the one most subject to wear and tear 'by ,the effect of hot powder gases.

To avoid the necessity of replacing from time to time the entire muzzle part of the barrel, a riiled liner vr7 is exchangeably fitted in this part. The liner-isl secured in its axial position by va circumferential ange 8 at the rear end of the liner which'engages in a` corresponding circumferential groove in Vthe rear end of muzzle part '1. For the purpose of maintainingin registrythe riingo'f the 'liner and the riiling of muzzle .part 1, the liner is held against rotation relative to the barrel by circumferentially spaced locating or locking pins 9. The forward end of the liner abuts against a ange 1 of barrel part 1.

The liner and its locking pins can be conveniently assembled from the rear end of muzzle part 1 when the latter is detached from the breech part of the barrel.

As previously explained the liner, due to its location in the barrel, is the part subjected to the greatest wear. Accordingly, the liner is preferably made of a material that is as resistant as possibleI to the effect of the hot powder gases. Generally, the material used for the liner is of a higher quality than the material used for the barrel parts 1 and 2. The length of the liner is selected according to the calibre of the gun and the length of projectile 10 of the cartridge. Generally speaking, the length of the breech part of the barrel is approximately the same as that of the casing or the increment of a cartridge rammed into the barrel.

The breech part is provided with external threads 12 by means of which the breech ring is attached to the barrel. The muzzle part of the barrel is provided with a circumferential support flange 13 situated adjacent to the forward end of the sleeve 3.

The gun barrel according to Fig. 2 is basically similar to the barrel of Fig. l with the exception that with the barrel of Fig. 2 the liner 7 is integral with the breech part 2. The two barrel parts are joined by screwing the internal threads 4' of locking sleeve 3 on the external threads 5' of muzzle part 1.

It will finally be apparent that the separate sleeve member 3 of Fig. l could be used with the liner arrangement of Fig. 2.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention it will be understood by those skilled in the art after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A gun barrel comprising a separate muzzle part and breech 'part in aligned abutment forming the chamber for a cartridge rammed into the barrel, a liner removably tted in said muzzle part and extending from the end thereof abutting the breech part toward the muzzle of the barrel to a point slightly ahead of the noze of the projectile of a rammed cartridge, and joining means detachably joining the said parts in aligned position.

2. A gun barrel comprising a separate muzzle part and breech part in aligned abutment, said breech part including the chamber of the barrel and having an axial length approximately equal to the length of the casing of a cartridge rammed into the barrel, a rifled liner removably tted in said muzzle part and extending from the end thereof abutting the breech part toward the muzzle of the barrel to a point slightly ahead of the nose of the projectile of a rammed cartridge, and joining means detachably joining the said separate parts in aligned position.

3. A gun barrel according to claim 2, wherein the said liner and the end of the muzzle part abutting the breech part are formed with a circumferential ange and a groove respectively engaging each other for securing the liner in a fixed axial position within the muzzle part.

4. A gun barrel according to claim 3 in combination with locking means tted between said liner and said muzzle part preventing a rotation of said liner relative to the muzzle part from retaining in registry said barrel rifling and said liner rifling.

5. A gun barrel according to claim 2, wherein the forward end of said breech part is continued by a ried sleeveshaped extension extending from said forward end into the abutting end of the muzzle part, the said extension constituting said removable liner.

6. A gun barrel according to claim 1, wherein said joining means comprise a sleeve member encompassing the abutting ends of said two separate parts of the barrel and secured to the end of each respective barrel part.

7. A gun barrel according to claim 6, wherein the said sleeve member is in form of an axially elongated ring having an internal thread, said abutting ends of the barrel parts each having an external thread engageable with the ring thread.

8. A gun barrel according to claim 6, wherein the said sleeve member is in form of an extension flange extending from one of said separate barrel parts, the said flange overlying the respective end of the other barrel part.

9. A gun barrel according to claim 8, wherein the said extension ange has an internal thread, the respective end of said other barrel part having an external thread engageable with the flange thread.

10. A gun barrel according to claim 1, wherein the said joining means comprise a sleeve member encompassing the abutting ends of said two separate parts ofthe barrel and secured to the end of each respective barrel part, and wherein locking means secure the said sleeve member against rotation relative to the barrel.

References Cited in the flle of this patent UNITED STATES PATENTS 898,908 Mertens Sept. 15, 1908 1,234,783 Mauser Iuly 31, 1917 2,609,631 Garand Sept. 9, 1952 2,635,021 Alward Apr. 14, 1953 FOREIGN PATENTS 896,501 France May 2, 1944 

